C#改变系统音量

通过模拟音量键输入方式实现

[DllImport("user32.dll")]
static extern void keybd_event(byte bVk, byte bScan, UInt32 dwFlags, UInt32 dwExtraInfo);

[DllImport("user32.dll")]
static extern Byte MapVirtualKey(UInt32 uCode, UInt32 uMapType);

private const byte VK_VOLUME_MUTE = 0xAD;
private const byte VK_VOLUME_DOWN = 0xAE;
private const byte VK_VOLUME_UP = 0xAF;
private const UInt32 KEYEVENTF_EXTENDEDKEY = 0x0001;
private const UInt32 KEYEVENTF_KEYUP = 0x0002;

/// <summary>
/// 改变系统音量大小，增加
/// </summary>
public static void VolumeUp()
{
keybd_event(VK_VOLUME_UP, MapVirtualKey(VK_VOLUME_UP, 0), KEYEVENTF_EXTENDEDKEY, 0);
keybd_event(VK_VOLUME_UP, MapVirtualKey(VK_VOLUME_UP, 0), KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0);
}

/// <summary>
/// 改变系统音量大小，减小
/// </summary>
public static void VolumeDown()
{
keybd_event(VK_VOLUME_DOWN, MapVirtualKey(VK_VOLUME_DOWN, 0), KEYEVENTF_EXTENDEDKEY, 0);
keybd_event(VK_VOLUME_DOWN, MapVirtualKey(VK_VOLUME_DOWN, 0), KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0);
}

/// <summary>
/// 改变系统音量大小，静音
/// </summary>
public static void Mute()
{
keybd_event(VK_VOLUME_MUTE, MapVirtualKey(VK_VOLUME_MUTE, 0), KEYEVENTF_EXTENDEDKEY, 0);
keybd_event(VK_VOLUME_MUTE, MapVirtualKey(VK_VOLUME_MUTE, 0), KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0);
}